Array flat() and flatMap()
    The flat() and flatMap() methods for arrays creates a new array such that each nested array item is concatenated into it.
  
Status
  
    
    
    Baseline Widely Available (since 2022-07-15)
  
    
    
  MDN documentation
Specifications
- ECMAScript® 2026 Language Specification (#sec-array.prototype.flat), from TC39 (Ecma International).
 - ECMAScript® 2026 Language Specification (#sec-array.prototype.flatmap), from TC39 (Ecma International).
 
Browser support (view on caniuse.com)
- Chrome 69 Released on 2018-09-04
 - Chrome Android 69 Released on 2018-09-04
 - Edge 79 Released on 2020-01-15
 - Firefox 62 Released on 2018-09-05
 - Firefox for Android 62 Released on 2018-09-05
 - Safari 12 Released on 2018-09-17
 - Safari on iOS 12 Released on 2018-09-17
 
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